Терапевтический архив (Dec 2011)
Clinicofunctional assessment of electric cardiac unstability in diastolic dysfunction of the left ventricle in patients with coronary heart disease
Abstract
Aim. To study parameters characterizing electric myocardial unstability in coronary heart disease (CHD) patients with different variants of diastolic dysfunction (DD) of the left ventricle (LV). Material and methods. The study included 86 outpatients (26 females, 60 males, mean age 57,3 ± 5,6 years) who had myocardial infarction (MI) more than 1 year before the trial with stable course of CHD during a previous month, LV ejection fraction more than 45% and with a stable sinus rhythm. Group 1 consisted of 36 patients with abnormal LV relaxation, group 2 - of 28 patients with pseudonormal LV DD, group 3-22 patients with a restrictive type of LV DD. The following examinations were made: Holter ECG monitoring, echocardiography, signal-average ECG with isolation of late ventricular potentials (LVP), estimation of heart rate variability, ventricular repolarization (Q-T interval dispersion, corrected interval Q-T). Results. The following variants of LV DD were detected: type 1 - 42%, type 2 - 32,5%, type 3 - 25,5%. LV DD progression was accompanied with enhancing vegetative imbalance and sympathetic activity: in the group with abnormal relaxation - in 52,5% patients, in the group with a restrictive type - in 93,3%. CHD patients with restrictive DD had more frequent LVP (chi-square = 4,1; p < 0,05) and visualization of anomalous contractility zones (60%), ventricular extrasystole (VE) was registered in 100% cases (VE of grade IV-V in 43,3%), QTc and QTd were higher than threshold - 450.2 ± 5,4 and 71,2 ± 6,5 ms. Conclusion. Because of multifactorial genesis of electric unstability, perfection of diagnosis and prognosis of risk in CHD patients with aggravation of LV DD demands a complex analysis of parameters respecting functional condition of the myocardium, relations between electric and structural-geometric remodeling of the heart.